Mike Rylander <mrylander@gmail.com> writes:
> As a side note, wouldn't the in-memory bitmaps pretty much kill the
> need for multicolumn indexes? It seems that they would be able to
> join index scans on the same table, and then there would be no need
> for industrial strength cross-column correlation stats.
No, because the ability to do it is not the same as the ability to
predict in advance how many rows will result.
regards, tom lane